POS0630 INCIDENCE AND ASSOCIATED FACTORS OF CANCER IN PATIENTS WITH RHEUMATOID ARTHRITIS
Authors: O. Tasci, M. Aysin, D. Sahin Eroglu, A. K. Aydogan, A. Ateş, T. M. Turgay, G. Kinikli
Journal: Annals of the Rheumatic Diseases (2022)

Background Rheumatoid arthritis (RA) is an autoimmune disease primarily characterized by joint inflammation along with systemic manifestations and increased risk of cardiovascular disease. Furthermore, it has been suggested that RA itself and medications administered might increase the risk of cancer. Objectives To assess cancer incidence in RA patients and factors associated with cancer development in RA patients. Methods In this single centre retrospective cohort study, the data of 2000 patients (76.3% female, mean age at the last follow-up: 59.5 ± 13.4 years) who were followed up between 2005 and 2020 and fulfilled 2010 ACR/EULAR classification criteria were scrutinised. Patients’ demographic, clinical and serological characteristics, and smoking history were recorded. Multivariable logistic regression analysis was performed to determine the associated factors with cancer development. The standardized incidence rate (SIR) was calculated by dividing the number of cancer cases observed in a given age and gender group by the expected number. Results After a median follow-up of 9 years, 71 (3.6%) patients were diagnosed with cancer and the number of patients with more than one malignancy was 5 (0.5%). Cancer types in each sex were demonstrated in Table 1. Seropositivity rate of the cohort was 86.0% and 376 out of 1102 (34.1%) patients were smokers. Glucocorticoids were the most common used agent in the treatment of RA (75.2%), followed by methotrexate (68%), hydroxychloroquine (65.1%), sulfasalazine (37.7%), leflunomide (35.5%), biological disease-modifying antirheumatic drugs (11.4%) and tofacitinib 4%. In multivariable logistic regression analysis performed of 1102 patients without missing data of smoking history, only smoking and age were independently associated with malignancy (Odds Ratios were 2.11 (95% Confidence Interval (CI) 1.07-4.14 and 1.05 (95% CI 1.02-1.07), respectively). Treatment modalities and RA-related clinical factors were not related to cancer development (data not shown). When compared with the 2017 Cancer Statistics of Turkey, the incidence of malignancy in our RA cohort was similar to the corresponding age and gender groups. The SIRs in male and female patients were calculated as 0.93 (95% CI: 0.82-1.05 p= 0.25) and 0.92 (95% CI: 0.77-1.09 p= 0.34), respectively. Table 1. Number of malignancy distribution by gender of patients Female Male n=47 n= 24 Breast, n (% )* 15 (100.0) 0 (0.0) Urogenital system, n (% )* 8 (53.4) 7 (46.6) Prostate, n (% )* 0 (0.0) 5 (100.0) Lung, n (% )* 3 (30.0) 7 (70.0) Lymphoma, n (% )* 4 (57.1) 3 (42.9) Thyroid, n (% )* 6 (100.0) 0 (0.0) Skin, n (% )* 5 (83.3) 1 (16.7) Colorectal, n (% )* 2 (50.0) 2 (50.0) Head and Neck, n (% )* 0 (0.0) 3 (100.0) Multipl Myeloma, n (% )* 1 (50.0) 1(50.0) Others, n (% )* 7 (87.5) 1 (12.5) *Row Percent Conclusion Our results show that patients with RA do not require additional screening beyond the nationally recommended guidelines. Medications used, including tumor necrosis factor inhibitors, did not increase the risk of cancer. In conclusion, all patients with RA should receive standard age- and sex-appropriate cancer screening. References [1]McInnes IB, G. Schett, The pathogenesis of rheumatoid arthritis. N Engl J Med 2011; 365: 2205-19. [2]De Cock D, Hyrich K. Malignancy and rheumatoid arthritis: Epidemiology, risk factors and management. Best Practice &amp; Research Clinical Rheumatology. 2018;32(6):869-86. Disclosure of Interests None declared